Denture.



No. 643,868. 7 Patented Feb, 20,. I900.

w. u. DWIGHT DENTURE.

(Application filed my 31, 1899.)

(No Model.)

lnvenlara UNITED STATES VILLIS H. DWIGHT,

PATENT OFFICE.

OF LE MARS, IOWA.

DENTU RE.

SPECIFICATION forming part of Letters IPatent No. 643,868, dated February 20, 1900.

Application filed May 31, 1899.

T0 aZZ whomit may concern.-

Be it known that I, WILLIS H. DWIGHT, of Le Mars, in the county of Plymouth and State of Iowa, have invented certain new and useful Improvementsin Dentures; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, and to the letters of reference marked thereon, which form a part of this specification.

This invention relates to improvements in dentures or artificial teeth; and the invention consists in the matters hereinafter set forth, and more particularly pointed out in the appended claims.

In the drawings, Figure 1 is a front elevation of a facing which constitutes the artificial tooth, the same being much enlarged. Fig. 2 is a vertical section taken on line 2 2 of Fig. 1, showing the relation of the facing to the backing or supporting-bridge and the devices for attaching the facing to the said backing. Fig. 3 is a view of the attachingpin removed from the facing. Fig. 4 shows two views of one form of socket-piece which is contained within the socket of the facing which is engaged by said attaching-pin. Fig. 5 shows the attaching-pin connected with the platinum backing-plate'as it appears in one stage of its manufacture. Figs. 6 and 7 show two views of a modified form of attaching-pin. Fig. 8 shows a modified form of socket-piece for the socket in the facing. Fig. 9 is a blank from which said socket-piece is made. Fig. 10 shows another modified form of socketpiece. Fig. 11 illustrates the blank from which the socket-piece shown in Fig. 10 is made. Fig. 12 shows a modified construction of the means for connecting the attaching-pin with the backing, and Fig. 13 shows a further modification of the attaching-pin and means for connecting the facing and backing thereby.

As shown in said drawings, A designates a porcelain plate which is made of the form of the tooth of which it is to take the place and which is known in the art as a facing.

B designates as a whole a bridge or backing to which the facing A is attached and which backing is secured to supportingcrowns or roots in the mouth. The backing shown in Fig. 2 is of composite structure, con- Serial No. 718,812. (No model.)

sisting of two connected partsa thin plate 13, preferably made of platinum, and a body B of metal which will not be corroded by the acids of the mouthsuch, for instance, as gold. Said backing is formed by burnishing a sheet of platinum to the lingual face of the facing and flowing with the gold to the proper thickness. Said backing or bridge B is usually made in sections, one section for each tooth or facing, and where more than one section is required the sections are united rigidly by soldering or like means to provide a bridge or backing of the required length.

0 designates a pin by which the facing is attached to the bridge or backing. As shown in Fig. 2, said pin is connected rigidly with the backing and engages a rearwardly-opening socket A in the rear face of the facing. The end or shank c of said pin is inserted through a central opening in the backingplate B and has interlocking engagement with the body 13 of the backing, and the parts become firmly united when the gold is flowed over the same. Said shank cis desirably somewhat reduced in diameter and is made cylindrical and provided with screw-threads or has its exterior surface otherwise roughened to provide the proper interlocking engage- 8o ment thereof with the metal forming the backing. Said socket A is of undercut construction or wider at its inner side than at the outer side thereof and is herein shown as of dovetail form in longitudinal section. The vertical length of said socket is somewhat greater than its width, and the inclined walls of the socket are its upper and lower walls. The attaching-pin G is made of a metal possessing some resiliency, such as a mixture of gold and platinum, which is known in the art as platinized gold. Said attaching-pin is provided at its end which engages said socket with laterally-separated divergent springarms 0 c, which are so shaped on their outer faces as to closely fit the inclined walls of the socket when inserted thereinto, as shown in Fig. 2. Said pin Ois preferably made hollow, as indicated in Figs. 2 and 3.

The undercut socket A will desirably be provided with a socket-piece A forming a lining therefor. The form of socket-piece shown in Fig. 2 and which is shown removed from the facing in Fig. 4 consists of a meshown in Fig. 2.

tist.

tallic strip having a high fusing-point, such as platinum, and comprises a central section a, which engages the bottomv of the socket, and two end sections a, which are inclined to the central section and are in contact with the inclined walls of said socket, as clearly The socket-piece C will desirably be baked in the porcelain facingthat is to say, said socket-piece will be placed in the facing when the same is molded, so that when the porcelain is hardened by the action of heat in the baking-oven the socket-piece will be made a permanent part of the facing and cannot be withdrawn so long as the facing remains intact. It is necessary, therefore, when said socket-piece is baked in the facing that it be made of a metal whose fusing-point is above the fusing-point of the porcelain. Said socket-piece gives to the interior of the socket a smooth finish and a symmetrical form for engagement with attaching-pin. In the manufacture of the denture the socketpiece is made to accurately fit the diverging arms of the attaching-pin, so that when said socket-piece is placed in the backing and baked therein no cutting or re-forming of the parts will be required to accurately fit the pin within said socket. Moreover, said socketpiece serves to reinforce or strengthen the facing.

The method of assembling the part of the denture described is as follows: In practice when the bridge or backing is furnished at the same time the facing is put in place said backing will usually be constructed by the den- The method of constructing said backing is as follows: The attaching-pin will first be inserted into the socket with its shank projecting therefrom. The platinum plate 13 will then be trimmed to accurately lit the lingual surface of the facing and a hole punched to receive the shank of'the attaching-pin. Thereafter said backing-plate will be burnished to the said lingual surface of the facing in a familiar manner and said pin and backing-plate removed from the facing by grasping the shank of the pin with a suitable tool, the resiliency of the spring-arms c of said pin permitting the same to be readily withdrawn from said facing. The plate B and attached pin (shown in Fig. 5) willt-hereafter he placed in a horizontal position with its front face downwardly and said front face of the plate and the part of the'pin projecting from the same covered with a suitable investing material. The metal forming the main body B of the plate (which will usually be gold) is then applied in a molten state to the rear side of the plate by an operation called flowing, the rear surface of which is given the desired form, as shown in Figs. 2 and 5. Said investing material prevents the molten metal from passing between the shank of said pin and plate and collecting on that part of the attaching-pin which is adapted for engagement with the socket of the facing. Said body of metal B is made of such thickness as to completely cover the shank of the attaching-pin, which projects through the plate B. That molten metal flows over and closely invests the plate and roughened shank, and when hardened it will be seen that the pin and backing-plate are united firmly thereto.

The backing is now in condition to attach the facing thereto. The socket A of said facing at the time said facing is to be attached to the backing with the pin thus connected therewith will be filled with a suitable cement, and the spring-arms of the pin 0 will be inserted thereinto by pressing the facing upon said pin, and said arms will be pressed together,so as to permit them to pass through the narrow part of said socket. When said pin is inserted fully into said socket, the arms a will expand by their own resiliency into contact with the inclined end walls of the socket, and said pin cannot be withdrawn from the socket so long as said arms are main tained in their normal separated positions. The outer ends of the arms 0 are beveled, as shown, to facilitate the entrance of the pin into the socket. When the body of cement within the recess, which is designated by the letter D, is hardened, it holds the arms of said attaching-pin separated and in contact with the inclined side walls of the recess, in which position said pin is effectually held from withdrawal from the recess. In the form of attaching-pin wherein the same is made tubular, as shown in Fig. 2, the body of the cement will pass through the tubular shank of the pin and be in contact with the body 13 of the backing and will serve as an additional means of firmly uniting the facing to the back. vAny excess of cement contained in said recess when the facing is pressed into place will be forced outwardly between the facing and plate .B", so it will be excluded therefrom.

Desirably a thin sheet A of soft metal, such as moss or soft gold, will be interposed between the lingual surface of the facing and the platinum plate B, which serves to close the space between said parts and prevent access of the fluids of the mouth to the cement D. Said sheet A also serves to fill in any irregularities in the surfaces of the plate and facing and forms a continuous joint between the same. The shank c of the pin is herein shown as provided with screw-threads, but in the operation just described it may be otherwise roughened or barbed in order to afford the required interlocking engagement with the gold or other metal of the body B which is flowed thereover. It will be noted that at the time the molten metal of the body B of the bridge or backing is flowed over the platinum backing-plate the porcelain facing is entirely removed from the same, so that it is not subjected to the heat of such process, which in the methods of attachment heretofore commonly employed often fractures the porcelain facing.

\Vhen the facing is to be applied to a bridge which is already in position, said bridge will be provided at the proper place therein with an aperture of proper size, into which the shank c of the attaching-pin is adapted to be inserted. In this instance said aperture in the backing will desirably be screw-threaded, and the shank of the pin will be screw-threaded for engagement with the same. If desired, cement may be applied to said parts before the shank of the pin is inserted into said aperture. The attachment of the facing to the pin which is thus united to the bridge or backing will be the same as that heretofore described.

When a facing attached as thus described becomes injured by a fracture or it is desired for other purposes to replace the same, it will be removed and the body of cement D loosened and detached from the pin, when a perfect facing may be applied in the manner above described. It will be seen, therefore, that in this operation the attachment of the pin 0 to the backing need not be disturbed.

The attaching-pin may be of other form than shown in Figs. 2 and 3. For instance, the shank of said pin and the part thereof which form the spring-arms may be made of two separate parts, as shown in Figs. 6 and 7. As shown in said figures, E designates a screw, and E a strip of metal, which is provided centrally thereof with an opening, through which said screw passes, and the opposite ends e e of which strip are bent at an angle to said central portion of the strip on the side opposite to the shank of the screw to form springarms which are adapted for engagement with the socket of said facing. The outer ends of said arms are beveled, as in the construction of the pin O.

In Figs. 8 and 9 is shown a modified forln of socket-piece for the socket of the facing. Said socket-piece, which is designated by the letter F, is generally similar to that shown in Fig. 4, and comprises a middle section fand end sectionsff,which are bent at an angle to said middle section to conform to the inclination of the inclined walls of said recess. Said end sections f are provided with marginal flanges f which when in place within the recess A project beyond the walls of the socket into the material forming the facing and provide an increased area of contact between said socket-piece and the body of the facing,which aids to hold the former in place in said socket. Said socket-piece is made from sheet metal by the use of suitable cutting and swaging dies. The blank from which the lining is made is shown in Fig. 9 and the dotted lines thereon indicate the places at which the metal is to be folded to form the completed structure.

In Figs. 10 and 11 is shown another form of socketpiece which is made from sheet metal by cutting and swaging' dies. Said socket-piece has the form of a cup G, and co mprises a bottom wall g, side walls g g, and end walls g 9 which latter are inclined to conform to the inclination of the inclined end for engagement with slits 9 formed in the end walls g and near the side margins thereof. Said tongues when the sections forming the side and end walls of the cup G are folded together,as shown in Fig. 10,pass through said said slits and are folded on the outer surface of said end walls, as shown in said Fig. 10. Said end walls g are provided with flanges 9 which extend beyond the side walls g and are adapted to be embedded in the material. forming the facing when the cup is in place in said recess A. The dotted lines in Fig. 11 indicate the places at which the metal is folded when the same is bent to final form. Said socket-piece may be otherwise shaped as found most desirable.

In Fig. 12 is shown a modified construction of the means by which attaching-pin is connected with the facing-plate B. As shown in said figure, B designates the platinum backing-plate shown in Fig. 2, and B designates a thimble which is inserted in the central opening thereof and which is adapted to receive the shank of the attaching-pin. Said thimble is provided with interior screwthreads adapted to engage the screw-threads of the shank'of the attaching-pin and by means of which said pin is detachably connected with the backing. Said thimble is provided with an annular marginal flange b, which is adapted to overlap the plate around said opening therein and which limits the insertion of the thimble into said opening. Said thimble and the rear surface of said plate will be covered with a body of gold or like metal, as indicated in dotted lines in said figure, and by which said parts are secured together. Said thimble may, if desired, be made an integral part of said plate. This construction enables the pin to be readily removed from the backing in case of fracture of the same.

In Fig. 13 is shown a modification of the means for attaching the facing to the backing or bridge. In said figure H designates the facing and I the backing. Said backing is made from a solid piece of suitable metal and is not of composite structure, as that heretofore described. In this construction, however, the position of the attaching-pin is reversed-thatis to say, the backing is provided with a dovetail-shaped socket '5, into which is expanded one end of a spring-pin J, which is adapted for connection at its other end with a screw-threaded bolt K,which projects rearwardly from said facing and is shown as secured therein by being baked in the material forming said facing. As shown, said pin J is made tubular and is provided with internal screwthreads adapted to engage external threads on said bolt. Said facing is provided with an annular recess h, surrounding the bolt K, into which the adjacent end of the pin walls of the socket.

J fits,thereby enabling the backin g to be made of proper thickness and at the same time completely cover the expansible end of said pin. In attaching the facing to the backing by the construction herein shown the pin J will first be screwed upon the bolt K, and afterward said pin is forced into the recess 1 of the backing, which recess will have previously been filled with cement. When the cement hardens, it will hold said arms in their expanded position in engagement with the inclined side A soft-metal plate, like the plate A (shown in Fig. 2,) may beinterposed between said backing I and facing H.

The pin 0 or the modified forms thereof may obviously be employed for attachinga crown to a natural root, in which case the shank will be elongated to extend into the root the proper distance.

Instead of the usual cement employed by dentists to attach the pin to the denture or support, as the case may be, a material like gutta-percha may be employed, and when such material is employed the pin may be readily removed by heating the same to soften it.

The word cement as used herein and in the claims is not intended to be restricted to the adhesive material employed by dentists and commonly known as cement.

I claim as my invention 1. The combination with a denture and a support or backing, one of said parts being provided with an undercut socket, of a pin provided at one end with spring-arms which are adapted for engagement with said socket and provided at its other end with a roughened shank which is adapted for engagement with said other part, and a mass of cement investing said socket and the part of the pin contained therein.

2. The combination with a denture and a support or backing therefor, one of said parts being provided with an undercut socket, of a tubular pin provided on one end with springarms which are adapted for engagement with the socket and constructed at its other end for engagement with said other part, and a mass of cement investing said socket, the part of the pin therein contained, and also said tubular portion of the pin.

3. The combination with a denture provided with an undercut socket, of a pin for attaching the same to a support, a metallic socketpiece contained within said socket, springarms on one end of said pin which are held by their resiliency in contact with the walls of said socket-piece, a, roughened shank on the other end of the pin adapted for engagement with the support, and a mass of cement investing said socket and the part of the pin contained therein.

4:. The combination with a.denture and a support or backing, one of said parts being provided with an undercut socket, of a pin provided on one end with spring-arms which are adapted for engagement with said socket and constructed at its other end for engagement with the backing or support, and a mass of cement investing said socket and the part of the pin contained therein, said spring-arms being rounded on their outer ends to permit their ready insertion into said socket.

5. The combination with a facing provided on its rear face with an undercut socket, a pin comprising spring-arms which engage said socket, a shank which projects from the rear face of the facing, and a mass of cement investing said socket and the part of the pin contained therein, of a backing comprising a plate of suitable met-a1 which engages the rear face of the facing and through which the shank of the pin extends, and a body of metal which is flowed over the plate and covers said shank.

6. The combination with a denture provided with an undercut recess and a backing or support for the same, of a pin provided at one end with a roughened shank which is adapted for engagement with the backing or support and provided at its other end with springarms which are contained within said socket of the denture and which arms are held by their resiliency in contact with the walls of said socket, and a mass of cement investing said socket and the part of the pin contained therein.

7. The combination with a denture and a backing or support, of a pin connecting said denture and support and a sheet of soft metal interposed between the meeting faces of the denture and support.

8. The combination with a denture provided with a socket, of a socket-piece provided with a lateral flange which projects from said socket and is embedded in the material forming the denture.

9. The combination with a denture provided with a socket, a socket-piece contained within said socket and provided with a lateral flange which extends into and is embedded in the material forming the denture, and a pin engaging at one end said socket and adapted for connection at its other end with a support or backing.

10. The combination with a denture, provided with a socket of a socket-piece having integral bottom, end and sidewalls, lateral flanges on said walls which project from said socket and are embedded in the material forming the denture, and a pin engaging at one end said socket and adapted for connection at its other end with a support or backing.

In testimony that I claim the foregoing as my invention I afiix my signature, in presence of two witnesses, this 25th day of May, A. D. 1899.

WILLIS II. DWIGHT.

Witnesses:

WILLIAM L. HALL, GERTRUDE BRYCE. 

